Method for stripping coatings from optical fibers

Abstract

A method and apparatus are provided for removing protective coating material from a fiber optic cable including one or more optical fibers. A stream of hot inert gas is directed onto the cable to soften the protective coating material and blow it from the cable. The stream can be moved relative to the cable until the desired length of coating material has been removed.

What is claimed is:  
     
       1. An apparatus for removing a predetermined length of a protective coating material from an optical fiber, the optical fiber being a glass optical fiber having a surface surrounded by the protective coating material, the apparatus comprising: 
       a gas source;  
       a filter connected to said gas source, wherein said filter receives gas from said gas source and discharges filtered gas;  
       a heater connected to said filter, wherein said heater receives the filtered gas; and  
       a nozzle connected to said heater, wherein said nozzle receives the heated filtered gas from said heater, wherein said nozzle directs the heated filtered gas onto the protective coating of the optical fiber;  
       wherein the temperature and composition of the filtered gas are controlled such that the heated filtered gas does not react with the protective coating material to create a combustion residue on the surface of glass optical fiber when the heated gas is directed onto the protective coating material surrounding the glass optical fiber;  
       wherein the heater and nozzle are configured so that the temperature of the heated filtered gas is sufficient to soften the protective coating material without melting the protective coating material; and  
       wherein the velocity of the stream of heated filtered gas exiting said nozzle is sufficient to remove the protective coating material from the optical fiber.  
     
     
       2. The apparatus of claim  1  further comprising: 
       a device for inhibiting vibration of the optical fiber when the stream of hot gas is incident thereon.  
     
     
       3. The apparatus of claim  1  wherein the device for inhibiting vibration is comprises: 
       a first clamp affixed to the optical fiber; and  
       a second clamp affixed to the optical fiber and spaced from the first clamp.  
     
     
       4. The apparatus of claim  2  wherein the device for inhibiting vibration comprises: 
       a tube having an outlet end adjacent the stream of the hot gas, the optical fiber being received within the tube; and  
       a delivery device for conveying the optical fiber through the tube such that an exposed portion of the optical fiber is advanced through and projects from the tube so that the stream of hot gas may be incident thereon, while a remaining portion of the optical fiber is received within and supported by the tube.  
     
     
       5. The apparatus of claim  1  further comprising: 
       a motive device to move the stream of hot gas relative to the optical fiber.  
     
     
       6. The apparatus of claim  1  wherein the optical fiber has a longitudinal axis, the apparatus further comprising: 
       a motive device selectively moving the stream of hot gas along the predetermined length of the optical fiber generally parallel with the longitudinal axis as well as laterally relative to the longitudinal axis of the optical fiber.  
     
     
       7. An apparatus for removing a predetermined length of a protective coating material from an optical fiber, the optical fiber being a glass optical fiber having a surface surrounded by the protective coating material, the apparatus comprising: 
       a gas source;  
       a heater connected to said gas source, wherein said heater receives the gas; and  
       a nozzle connected to said heater, wherein said nozzle receives the heated gas from said heater, wherein said nozzle directs the heated gas onto the protective coating of the optical fiber;  
       a first guide tube disposed to receive the optical fiber; and  
       a delivery device for conveying the optical fiber through the guide tube such that a portion of the optical fiber is advanced through and projects from the first guide tube so that the stream of heated gas may be incident thereon, while a remaining portion of the optical fiber is received within and supported by the first guide tube;  
       wherein the temperature and composition of the heated gas are controlled such that the heated gas does not react with the protective coating material to create a combustion residue on the surface of glass optical fiber when the heated gas is directed onto the protective coating material surrounding the glass optical fiber;  
       wherein the heater and nozzle are configured so that the temperature of the heated gas being sufficient to soften the protective coating material without melting the protective coating material; and  
       wherein velocity of the stream of heated gas exiting said nozzle is sufficient to remove the protective coating material from the optical fiber.  
     
     
       8. The apparatus of claim  7  further comprising: 
       a second guide tube spaced apart from the first guide tube, wherein said second guide tube is disposed to receive the optical fiber from the first guide tube and the predetermined length of coating to be remove is disposed between the first and second guide tubes.  
     
     
       9. The apparatus of claim  8  further comprising: 
       a filter connected to said gas source and said heater, wherein said filter receives gas from said gas source and discharges filtered gas, wherein the filtered gas is received by the heater.